Abstract: The storage of viable seeds and the species diversity in the soil of six salinealkali communities dominated by one species in the alkalized meadow in the Song-Nen Plain of China are comparatively analyzed in this paper. The common feature of the three communities dominated by Chloris virgata, Sueda corniculata, and S. heterotera was that they had large seed banks, of which the majority was composed of the dominant species, and had lower species diversity index. The transitional communities dominated by Puccinellia tenuiflora and Aeluropus littoralis var. sinensis, respectively, showed medium seed bank and species diversity. The dominant species in the seed banks were the same as the aboveground dominant species in these two communities. The Aneurolepidium chinense community differed from other communities of differentiating successional stages, in that it had the smallest seed bank, and highest species diversity.